Canted coil spring shock absorber

ABSTRACT

A shock absorbing device having at least one canted spring disposed between two members is described. When the members move toward each other, the one or more canted coil springs are canted and compressed. The shock absorbing device takes advantage of the unique force-displacement curve of canted springs and reduces bounce back.

FIELD OF THE INVENTION

The field of the invention is shock absorption devices and methods.

BACKGROUND

The background description includes information that may be useful inunderstanding the present invention. It is not an admission that any ofthe information provided herein is prior art or relevant to thepresently claimed invention, or that any publication specifically orimplicitly referenced is prior art.

Some shock absorbing devices are known in the art, especially shockabsorbing devices used in shoes. For example, Adidas makes a shoe calledthe Springblade™ Drive M Running shoe. That shoe is made up of aplurality of cantilevered beam springs. As another example, Z-Coil makesa spring-loaded shoe that has coil springs disposed in the heel portionof the shoe. Yet another example is the company Spira has created a shoeusing what it calls WaveSpring® technology. Spira shoes often have onespring disposed in the heel portion of the shoe and two other springsdisposed in the forefoot portion of the shoe.

All publications identified herein are incorporated by reference to thesame extent as if each individual publication or patent application werespecifically and individually indicated to be incorporated by reference.Where a definition or use of a term in an incorporated reference isinconsistent or contrary to the definition of that term provided herein,the definition of that term provided herein applies and the definitionof that term in the reference does not apply.

While the prior art devices provide some advantages for absorbing shock,the prior art fails to provide a shock absorption configuration thatutilizes the unique load-deflection characteristics of a canted coilspring. For a description of the load-deflection characteristics ofcanted coil springs, see U.S. Pat. Nos. 3,468,527, 4,876,781, 4,893,795,4,974,821, EP0469489, EP0491258, EP0890758.

Thus, there is still a need for improved shock absorption devices andmethods.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1A is a cross sectional view of a canted coil spring having asingle axis of compressibility with an accompanying force versus anglegraph for a given constant displacement.

FIG. 1B is a cross sectional view of a canted coil spring having twoaxes of compressibility with an accompanying force versus angle graphfor a given constant displacement.

FIG. 2 is a top plan view of two canted coil springs disposed on asubstrate.

FIGS. 3A-3D is a top plan view showing different configurations forcanted coil springs.

FIG. 4 is a perspective view of a member having two canted coil springsthat are angled in opposite directions.

FIG. 5 is a perspective view of a member having two canted coil springsthat are angled in the same direction.

FIG. 6 shows a side view of a shock absorption device having a movementguide.

FIG. 7 shows a side view of a shock absorption device having no movementguide.

FIG. 8 shows a side view of a shock absorption device where the membersare hingedly coupled with an offset.

FIG. 9 shows a side view of a shock absorption device where the membersare hingedly coupled without an offset and where the canted coil springis formed as a wedge.

FIG. 10 is a shoe having a shock absorption device in the heel portion.

FIG. 11 is a shoe having a shock absorption device in the mid-footportion.

FIG. 12 is a shoe having a shock absorption device in the forefootportion.

FIG. 13 shows a member having channels to nest two linear canted coilsprings.

DETAILED DESCRIPTION

The following description includes information that may be useful inunderstanding the present invention. It is not an admission that any ofthe information provided herein is prior art or relevant to thepresently claimed invention, or that any publication specifically orimplicitly referenced is prior art.

The following discussion provides many example embodiments of theinventive subject matter. Although each embodiment represents a singlecombination of inventive elements, the inventive subject matter isconsidered to include all possible combinations of the disclosedelements. Thus if one embodiment comprises elements A, B, and C, and asecond embodiment comprises elements B and D, then the inventive subjectmatter is also considered to include other remaining combinations of A,B, C, or D, even if not explicitly disclosed. In one aspect of theinventive subject matter, the inventors contemplate a shock absorbingdevice having three key components: two members and at least one cantedcoil spring. The two members are movably coupled to one another andpreferably formed into generally flat pieces with at least one, butsometimes two or more, canted coil spring disposed between them. Whenthe members are moved toward each other by application of force,pressure, or displacement, the one or more canted coil spring compressesalong one or more axes of compressibility unique to those springs.

A canted coil spring, sometimes called a slanted coil spring, is acoiled spring formed such that the coils are all slanted at an angle(see, e.g., U.S. Pat. No. 5,108,078 describing some types of canted coilspring configured into circular shapes). Canted coil springs are uniquein that the springs respond to deflection by exhibiting a near-flatforce curve, similar to the spring response of a shape memory alloy.This unique response enables canted coil springs to be used in manydifferent applications where an ordinary spring that exhibits a linearforce-respond to deflection would not be adequate.

The axis of compressibility describes a radial axis of a canted coilspring along which compression is intended to occur based on the designof the spring. In springs having a single axis of compressibility, ifcompression force required to cause a particular deflection in thespring is graphed as a function of angle rotated about the longitudinalaxis of the canted coil spring, an angle of zero would result in aminimum on the graph. In springs having multiple axes ofcompressibility, on the other hand, if compression force required tocause a particular deflection in the spring is graphed as a function ofangle rotated about the longitudinal axis of the canted coil spring,each time an angle coincides with an axis of compressibility, a localminimum would appear in the graph. In all of the embodiments of theshock absorber described in this application, compression in the cantedcoil spring occurred at least in part along the axis of compressibility.

FIG. 1A shows a cross-section of a spring 100A having a single axis ofcompressibility with an associated graph showing the force required toachieve a constant deflection as a function of angle as measured fromthe 0 angle, while FIG. 1B shows a cross-section of a spring 100B havingmultiple axes of compressibility with an associated graph showing theforce required to achieve a constant deflection as a function of angleas measured from the 0 angle. On each of the graphs shown in FIGS. 1Aand 1B, the minimum/local minima correspond to compression directlyalong an axis of compressibility.

As mentioned briefly above, the members can be formed into opposingplates, or plate-like structures having one or more canted coil springsdisposed between them (sometimes referred to as “members”). In someembodiments the canted coil springs are both linearly configured andpositioned between the plates such that they are parallel to oneanother. FIG. 2 shows a top view 200 of two springs 202A and 202Bresting in such a configuration. When looking at FIG. 2, the coils ofboth springs 202A and 202B could be slanted so that the tops of bothsprings (assuming the view in FIG. 2 is a top view) are slanted eitherupward or downward. For example, FIG. 5 shows a perspective view of aconfiguration 500 where the springs 502A and 502B are slanted in thesame direction. In some embodiments, the springs 502A and 502B should bedisposed symmetrically to one another according to a line of symmetricbetween the two. In other embodiments, the springs 502A and 502B can bedisposed symmetrically to one another according to a line of symmetrythat also divides the members symmetrically.

In still further embodiments having at least two canted coil springsdisposed between the plates, the canted coil springs are positioned andoriented between the plates such that their coils are slanted inopposite directions. FIG. 4 shows a perspective view 400 of two cantedcoil springs 402A and 402B that are slanted in opposite directions.

Although in some embodiments, as mentioned above, the canted coil springcan be linearly configured (as seen in FIG. 2), in other embodiments,the canted coil spring can be configured such that it is joined at theends (e.g., forming a loop or another circuit such as an oval, a square,a rectangle, etc.). Some possible axial canted coil springconfigurations 300 are shown in FIGS. 3A-3D. FIG. 3A shows a circularconfiguration 302, FIG. 3B shows an oval configuration 304, FIG. 3Cshows a rounded square configuration 306, and FIG. 3D shows a concentricconfiguration 308, wherein one spring is oriented concentrically to asecond spring.

FIG. 6 shows an embodiment 600 where the first plate 602 and the secondplate 604 are coupled to one another by a movement guide 606 comprisinga pin and a slot. Movement of the first plate 602 is restricted tomovement along the direction indicated by the arrows drawn onto FIG. 6.In some aspects, the members are not directly coupled to one another.FIG. 7 shows an embodiment 700 where the two members 702 and 704 arefree to move toward each other without restriction from a movementguide. This can be preferable in situations where freedom of movementbetween the two members 702 and 704 is important.

The members can be restricted in other ways than the movement guide 606shown in FIG. 6. In some embodiments, such as the embodiment 800 shownin FIG. 8, the members 802 and 804 are hingedly coupled and offset 808such that they are substantially parallel when they first come intocontact with the canted coil spring 806, while in other embodiments theyare substantially parallel when the members 802 and 804 have fullycompressed the canted coil spring 806. It is also sometimes preferableto have the members 902 and 904 hingedly coupled without the offset asshown in FIG. 9. In such an embodiment 900, it is preferable for thecanted coil spring 906 to similarly be wedge-shaped (e.g., in anuncompressed state as drawn).

One example of a real-world use for the shock absorption devicesdescribed in this application is in a shoe. Shoes 1000, 1100, and 1200,as seen in FIGS. 10-12, can be described as having a forefoot portion1002, a mid-foot portion 1004, and a heel portion 1006. The shockabsorbing device 1008 can be disposed in the heel portion (FIG. 10), themid-foot portion (FIG. 11), or the forefoot portion (FIG. 12). Any ofthe shock absorption devices described in this application can be usedin any portion of the shoe. In some embodiments, the shock absorptiondevice is removable and replaceable. For example, FIGS. 10-12 show ashoe having embodiments of a shock absorbing device similar to the onedepicted in FIG. 7. The shock absorbing devices shown in FIGS. 10-12could be swapped out for, as an example, any of the devices depicted inFIGS. 6-9 without damaging the shoe.

The principle behind enabling swapping of shock absorption devices is toenable a user to select a shock absorption device that exhibits specificdesired qualities. For example, different gauge wire can be used to formthe canted coil springs to affect how difficult it is to compress thespring.

Regardless of the embodiment, the canted coil springs of the shockabsorption device can be nested within one or more channel. FIG. 13shows a member 1300 having two channels 1302 and 1304 disposed on asurface. Two canted coil springs can fit within the channels 1302 and1304.

Various applications of the present inventive subject matter arepossible. For example, shock absorption devices can be used inorthopedic devices to encourage or resist different types of bone motionduring a person's gait. Contemplated shock absorption devices can alsobe used in running shoes to absorb shock while minimizing the amount ofbounce back.

As used herein, and unless the context dictates otherwise, the term“coupled to” is intended to include both direct coupling (in which twoelements that are coupled to each other contact each other) and indirectcoupling (in which at least one additional element is located betweenthe two elements). Therefore, the terms “coupled to” and “coupled with”are used synonymously.

Unless the context dictates the contrary, all ranges set forth hereinshould be interpreted as being inclusive of their endpoints andopen-ended ranges should be interpreted to include only commerciallypractical values. Similarly, all lists of values should be considered asinclusive of intermediate values unless the context indicates thecontrary.

As used in the description herein and throughout the claims that follow,the meaning of “a,” “an,” and “the” includes plural reference unless thecontext clearly dictates otherwise. Also, as used in the descriptionherein, the meaning of “in” includes “in” and “on” unless the contextclearly dictates otherwise.

The recitation of ranges of values herein is merely intended to serve asa shorthand method of referring individually to each separate valuefalling within the range. Unless otherwise indicated herein, eachindividual value is incorporated into the specification as if it wereindividually recited herein. All methods described herein can beperformed in any suitable order unless otherwise indicated herein orotherwise clearly contradicted by context. The use of any and allexamples, or exemplary language (e.g. “such as”) provided with respectto certain embodiments herein is intended merely to better illuminatethe invention and does not pose a limitation on the scope of theinvention otherwise claimed. No language in the specification should beconstrued as indicating any non-claimed element essential to thepractice of the invention.

Groupings of alternative elements or embodiments of the inventiondisclosed herein are not to be construed as limitations. Each groupmember can be referred to and claimed individually or in any combinationwith other members of the group or other elements found herein. One ormore members of a group can be included in, or deleted from, a group forreasons of convenience and/or patentability. When any such inclusion ordeletion occurs, the specification is herein deemed to contain the groupas modified thus fulfilling the written description of all Markushgroups used in the appended claims.

It should be apparent to those skilled in the art that many moremodifications besides those already described are possible withoutdeparting from the inventive concepts herein. The inventive subjectmatter, therefore, is not to be restricted except in the spirit of theappended claims. Moreover, in interpreting both the specification andthe claims, all terms should be interpreted in the broadest possiblemanner consistent with the context. In particular, the terms “comprises”and “comprising” should be interpreted as referring to elements,components, or steps in a non-exclusive manner, indicating that thereferenced elements, components, or steps may be present, or utilized,or combined with other elements, components, or steps that are notexpressly referenced. Where the specification claims refers to at leastone of something selected from the group consisting of A, B, C . . . andN, the text should be interpreted as requiring only one element from thegroup, not A plus N, or B plus N, etc.

What is claimed is:
 1. A shock absorption device for a shoe comprising:a first member movably coupled with a second member; and a first linearcanted coil spring disposed between the first member and the secondmember; wherein the first linear canted coil spring has a firstlongitudinal axis and comprises a first plurality of coils that arecanted with respect to the longitudinal axis; wherein the first cantedcoil spring has a first axis of compressibility that is oriented suchthat the first and second members cause compression along the first axisof compressibility upon movement of the first member toward the secondmember; and wherein the plurality of canted coils of the first linearcanted coil spring cause the first member to move (i) in a first lateraldirection as the first member moves toward the second member duringcompression of the first linear canted coil spring, and (ii) in a secondlateral direction opposite the first lateral direction as the firstmember moves away from the second member during decompression of thefirst linear canted coil spring.
 2. The shock absorption device of claim1, further comprising: a second linear canted coil spring comprising asecond plurality of canted coils and disposed between the first memberand the second member; and wherein the second canted coil spring has asecond axis of compressibility and is oriented such that the first andsecond members cause compression along the second axis ofcompressibility upon movement of the first member toward the secondmember.
 3. The shock absorption device of claim 2, wherein the firstlinear canted coil spring and the second linear canted coil spring arepositioned parallel to one another between the first member and thesecond member.
 4. The shock absorption device of claim 2, wherein thefirst and the second linear canted coil springs are oriented between thefirst member and the second member such that the first and secondplurality of coils are canted in the same direction.
 5. The shockabsorption device of claim 1, wherein the shock absorption device isdisposed in a heel of the shoe.
 6. The shock absorption device of claim5, wherein the first lateral direction is towards a rear of the shoe andthe second lateral direction is towards a front of the shoe.
 7. Theshock absorption device of claim 1, further comprising a movement guidethat prevents the first member from moving in a third lateral directionthat is perpendicular to the first and second lateral directions.
 8. Theshock absorption device of claim 7, wherein the movement guide restrictsthe first and second members from decoupling.
 9. A shoe comprising: aheel portion, a mid-foot portion, and forefoot portion; a first shockabsorption device disposed in at least one of the heel portion, themid-foot portion, and the forefoot portion; wherein the shock absorptiondevice comprises a first linear canted coil spring disposed between afirst member and a second member; and wherein the first linear cantedcoil spring is disposed between the first member and the second membersuch that the first member and the second member cause the first linearcanted coil spring to compress along its minor axis upon movement of thefirst member toward the second member; and wherein the minor axis isoriented relative to the first member and second member such that thefirst member moves in a first lateral direction upon decompression ofthe first linear canted coil spring; and wherein the first lateraldirection is towards the forefoot portion.
 10. The shoe of claim 9,wherein the shock absorption device further comprises: a second linearcanted coil spring disposed between the first and second members; andwherein the second linear canted coil spring is oriented symmetricallyrelative to the first canted coil spring.
 11. The shoe of claim 9,wherein at least one of the first and second members comprises a channelfor the first linear canted coil spring to rest in.
 12. The shoe ofclaim 9, wherein the first shock absorption device is removably coupledwith the shoe.
 13. The shoe of claim 12, wherein the first shockabsorption device is interchangeable with a second shock absorptiondevice having different spring properties.
 14. The shoe of claim 10,wherein the first linear canted coil spring and the second linear cantedcoil spring are positioned parallel to one another between the firstmember and the second member.
 15. The shoe of claim 10, wherein thefirst and the second canted coil springs (a) comprise first and secondpluralities of coils, respectively, and (b) are oriented between thefirst member and the second member such that the first plurality ofcoils and the second plurality of coils are canted in the samedirection.
 16. The shoe of claim 10, wherein the first and the secondlinear canted coil springs (a) comprise first and second pluralities ofcoils, respectively, and (b) are oriented between the first member andthe second member such that the first plurality of coils and the secondplurality of coils are canted in opposite directions.
 17. A device forstoring and releasing kinetic energy in a shoe comprising: a firstmember movably coupled with a second member; a first circular cantedcoil spring disposed between the first member and second member; asecond circular canted coil spring disposed between the first member andsecond member and oriented concentrically to the first circular cantedcoil spring; and wherein the first member and second member aresubstantially parallel to one another; wherein each of the first andsecond circular canted coil springs has an axis of compressibilityoriented in a normal direction to the first and second members such that(i) the first and second members move towards one another when the firstand second circular canted coil springs are compressed and (ii) thefirst and second members move away from one another when the first andsecond circular canted coil springs are depressed.
 18. The device ofclaim 17, wherein the first circular canted coil spring is canted in afirst circular direction.
 19. The device of claim 18, wherein the secondcircular canted coil spring is canted in a second direction that isopposite the first direction.
 20. The device of claim 18, wherein thesecond circular canted coil spring is canted in the first direction. 21.The device of claim 18, wherein the device is at least partiallydisposed within a heel of the shoe.